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Why is one of my DNS servers logging Event ID 4521 every 3 minutes for the last 2 months or more?

Medium Priority
Last Modified: 2012-05-06
I am having an authentication problem with a Windows 2000 machine (not server), and for whatever reason i looked at my primary DNS server. The DNS event log is full of Event ID 4521's that log every 3 minutes, and a few 3000 and 9999 (few and far between). My secondary DNS server, on the other hand, has no warnings at all. All i could find on this ID is to troubleshoot active directory. Anyone have any idea's? Log entry is below.

Event Type:      Warning
Event Source:      DNS
Event Category:      None
Event ID:      4521
Date:            2/17/2009
Time:            9:52:39 AM
User:            N/A
Computer:      SERVER3
The DNS server encountered error 9002 attempting to load zone . from Active Directory. The DNS server will attempt to load this zone again on the next timeout cycle. This can be caused by high Active Directory load and may be a transient condition.

For more information, see Help and Support Center at http://go.microsoft.com/fwlink/events.asp.
Watch Question

It looks like you might have a corrupt DNS zone. The "." zone is one that usually contains information about your local domain and helps to identify other domain controllers in your environment, and may also contain information about forwarders that resolve lookups in other domains.

Here is an article about how to correct this issue on a Windows 2000 Server:

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